An unfortunate novelty which will not attract followers. Carlsen believes that he has the time to cover his kingside but forgets the opposite wing.
9... g4f2 This is what the line is all about. Carlsen needs to choose carefully. 10. c3a4 The only move. 10... b6c7 Also an only move by Arjun, as the queen needs to hit the h2-pawn as well as the g3-square. 11. a4c5  11... f2h1 